Means for making castings by air-pressure.



0. J. SAYERS.

MEANS FOR MAKING GASTINGS BY AIR PRESSURE.

APPLIUATIOH FILED JULY 16, 1907. q

' Patented Oct 2 SHEETS-SHEET 1.

Jill

INVENTOR.

WITNESSES,-

0. J. SAYERS. I MEANS FOR MAKING GASTINGS BY AIR PRESSURE. APPLICATIONFILED JULY 16, 1907.

937,964. Patented 001;. 26; 1909.

2 SHEETS-SHEET 2.

UNlTEl) STATES PATENT OFFICE.

ORRIN J. SAYERS, OF CLEVELAND, O I -IIO, ASSIGN'OR TO RICHARD B. MOSERAND'FRED- ERICK J. LANGER, BOTH 0F CLEVELAND, OHIO.

MEANS FOR MAKING CASTINGS BY AIR-PRESSURE.

Specification of Letters Patent.

Patented Oct. 26, 1909.

Application filed July 16, 1907. Serial No. 384,016.

To all whom it may concern:

lie it known that 1. Oman J. Saunas, a citizen of the United States,residing at Cleveland. in the county. of ()uyahoga and State of Ohio,have invented a new and useful Means for Making Castings by Airlressure,of which the following is a specification.

.\l v invention relates to means for making castings by air pressure,and the invention comprises the means substantially as herein shown anddescribed and more particularly pointed out in the claims.

As shown, my invention is especially adapted for making relatively smallcastings of gold, silver and like metals by air pressure andparticularly for dental pur poses,such for instance as fillings forteeth, or for crowns, floors, backing's, plates or bridges for teeth.The invention is not necessarily limited to this class of work, but ispreferably described therewith to more clearly define its chief object,and because such castings must be exceptionally perfect to be ofpractical use and value. Obviously, other ob ects enter into the make upof the device to simplify the. casting operation and to make asubstantially self-operative machine easy to control and handle, and allas hereinafter more specifically set forth.

In the accompanying drawings, Figure 1 is a perspective view of myinvention with a blow-pipe in operation, and showing both under handcontrol. Fig. 2 is a sectional view of a flask with a mold therein foreasting a tooth filling such for example as shown in Fig. 3, said Fig. 3being a erspective view of the casting as it comes rom the mold, gateand all, and showing its-relative place in a molar (dotted lines). Fig.4 is a sectional view of a larger flask prepared for casting a backingto a porcelain facing, and Fig. 5 is'a perspective view of the tooththus built up and ready to be attached to the root, except that the gateleft by the casting operation has not been removed. Fig. (3 is asectional view of a still larger flask having an investing or mold for abridge casting. Fig. 7 is an edge elevation of a porcelain tooth havinga floor and pin cast thereto, the root of the tooth being shown indotted lines. Fig. 8 is a plan view of my device with its cover-open andshowing a flask seated therein, and Fig. 9 is a side elevation thereofwith the cover partly sectioned away to show the locking bolt whichholds it open. Fig. 10 is a longitudinal section centrally of the devicewith the cover. closed and an valve open, but showing the air valve,intake nipple, and various other parts inplain elevation to more clearlybring out their inclividual conformation and also their-relation to thebody of the device and cover. .In this view, a sectional view of a flaskand mold is also shown as seated above the vent opening in the bottom ofthe device and with a casting therein as it appears when completed. Fig.11 is a sectional viev. of the rear portion of the device showing amodified form of valve and means to automatically open andclose thesame.

In detail, the invention consists of a flask confining receptacle -2 ofany desired shape or f0rm,.but preferably constructed as shown with aflat'rectangular base 3- and walled body l of circular outlinecontaining a relatively large chamber 5 open at itstop and having asmoothly finished flat bottom 6- upon which various sized ring-shapedflasks A may be removably seated A horizontally swinging cover or cap -7is pivotally secured to the top and at one side of body 4 by screw 8mounted within stud -9 centrally within circular recess 10- of thesmaller circular portion -11- of the body. The contacting surfaces ofthe cover and the body are smoothly finished to make an air tight fit,-and moreover, said cover is provided with a in or handle 12 at its frontedge which is adapted to enter open slot -1'5 in the upper end of stopplate l4 s..- oured to the front of body i and to engage its upperbeveled edge -16 to press pin or handle 12 down and thereby force cover7 to its seat, and serving also to hold the cover seated as against airpressure from below. The foregoing clamping means is simple andelfective for a small device such as shown, but in a larger devicesuitable adjustable means for taking up wear may be employed therewith,as is obvious.

Cover 7- is opened by means of handle 12 and when fully open as seen inFigs. -9-- and --10, a springpressed bolt 13 mounted on end within avertical of the operator.

. from bolt ---13-- through side slot -19,- in

body portion l1---, and when thus released cover 7--- will closeautomatically under tension of coiled spring -2 0 located within recess10 and which spring has right angled ends engaged with the cover and thebody, respectively. The closure of the cover is practicallyinstantaneous and should be quick and responsive and Without undueeffort on the part of the operator because his attention and time ismainly occupied at this period in directing the flame from blow-pipe -B,see Fig. 1, upon the metal to be melted, and in watching the metal cometo a. boiling or molten condition. As soon as this occurs promptmeasures must be taken to force the metal while molten into the mold,and this result is brought .about by the release of the cover and-itsautomatic closure by spring 20. Thus, as cover '7- swings over chamber-5--, bolt opening 17- comes to rest directly over a second verticalbore '-2l in the rear end of body portion 11 and wherein a sliding valve22 of bolt shape is seated. This valve has an elongated and reducedupper end 23- adapted to bear against the bottom face of cover 7- duringits movement and whereby the valve is held in closed position andprevented from springing up under the pressure of coiled spring --2l' inthe bottom of bore 21 until opening 17 is reached. Lifting of the valveby the spring opens air passage 27- leading from intake nipple -28 tochamber -5 and allows air under pressure to discharge into chamber -5the moment cover 7 is closed and tightly locked. The sudden inrush ofair into closed chamber 5- Will force the molten metal into the moldcavity, more or less, but in order that the same may occur completelyand a perfect casting be obtained, I find that both the device and themold must be constructed with particular reference to a vent or relieffor the mold cavity.v To this end and for operative purposes, flask -A-is plac d within chamber 5 directly over vent passage -30 centrallylocated within bottom -6 and this passage may open into a supplementaryair chamber in the device, or communicate with the outer atmosphere fromand beneath base 3 as shown. Receiving chamber 5 is relatively largeenough to hold different sized flasks for different (kinds of work, andfor several reasons, I

predetermined size. In part, these reasons are convenience in handlingthe flasks, economy in the use of investing material,adaptability indrying or baking of the mold, and in removing the wax impression orpattern and also the casting from the mold. v

Now referring to the construction of the mold in particular. the bestcastings are obtained by using atleast two diiferent kinds (if investingmaterial for "the mold; namely. a finely ground or comparatively densematerial, and a coarse or comparatively porous material, the objectbeing to provide a smooth outer coating -31-- for the mold top and moldcavity, and a more or less porous backing or open body -3Q* for coating-31--. A thin layer of relatively dense and fine investing material forcoating ---31 contributes to the making of a smooth and deli-- air andgases in the mold cavity to escape during casting operations. and thecoarser and more porous body 32 sustains the said finer wall or coatingunder pressure and obviously gives greater freedom for the escape ofsaid air and gases to and through vent passage 30-.

However, I disclaim any novelty as to the use. of different moldmaterials for the purposes set forth, as the same is very common infoundry practice, nor doI lay claim to any special form of mold or flaskor method of making the mold, because various forms and kinds ofmoldsand flasks may be used with my invention. But for a better understandingof the operation of my device, I will briefly describe the making of amold for single casts, and follow with the making of the casting. Thus,taking a Wax model of the object. to be cast, the same is supported inthe center of the box or flask, such as a round flask A, by means of aneedle or wire, one sufficiently large enough to form an ingate -.35-.The fine molding material is then adhered carefully toall parts of themodel and its support, and when dry, a coarser mold-material is thrownin until the box is filled. The needle or ingate Wire is then withdrawnand the mold is burned and the wax model dissolved and removed. Themouth 34 of the ingate in the mold is also formed into a funnel or cupshape by the use of a founders spool, such as is ordinarily used forthis purpose.

Now having the flask and mold finished,

moving locking. end 23 from opening 17- in the cover. This accomplished,the tiask is seated upon bottom -6- and over vent passage'30- and theoperator places his gold or silver or other metal within the cup of theflask and directs a small pointed flame thereon, such as obtained by gasand oxygen from a hand controlled blow-pipe B, as shown. During thisoperation, the operator should be prepared with his lefthand to depresshandle -l8 of releasing bolt l3.. Then, at the critical moment when themetal becomes molten and before burning thereof occurs, instant releaseof the cover is brought about bya slightdown pressure of his finger andthe cover closes automatically and locks tightly and at the end of itsmovement permits valve -'22- to open-air passage 2T allowing air underpressure to fill chamber 5- and thereby force the molten metal into themold cavity, the trapped air or gases i'n'said cavity being forcedthrough the porous body of the mold and the vent or relief passage 30.

Either a rotary .or puppet-valve may be used in place of slide valve 22,and said valve or valves may be caused to close automatically by theopening movement of the cover. Such an arrangement is shown in Fig. 11,wherein rotary valve 38 limited to a quarter-turn or less, is adapted tobe closed by a coiled spring -39- when disengagement occurs betweenprojection 40 or its equivalent on the cover and pin t1- or itsequivalent on the valve. The primary opening movement of the cover cutsofl' the air before'ehamber -5 is opened, and again, when cover -7-closes, said closing movement at its end will open the valve against thetension of spring 39 and by the positive engagement be tween projection40 and pin 41.

\Vhat I claim is 1. In means for making castings by air pressure, anopen receptacle adapted to hold a flask and havin compressed airconnections, and automatic means adapted to close said receptacle.

2. In means for making castings by air pressure, an air compressordevice having a chamber adapted to confine a flask and selfclosing meansfor said chamber.

3. In means for making castings by air pressure, a flask receptaclehaving compressed air connections, and means to close the saidreceptacle constructed to control the air supply in combination with aflask adapted to be seated and air-confined within said receptacle.

4. In means for making castings by air pressure, a flask receptaclehaving compressed air connections, and automatic means to close thereceptacle and confine the flask therein and also to control the airsupply thereto.

5. In means for makin .castings by air pressure, a flask receptac ehaving a vent' opening for the flask and compressed air connections, andautomatic means to close said receptacle t0 confine the flask.

(i. In means for makin castings by air pressure, a flask receptac e.having a vent. opening for the flask and compressed all" connections,andautomatic means to close said receptacle and also to control the airsupply thereto.

7. .111 means for making castings by air pressure, a flask receptaclehaving compressed air connections and a movable member to close thesame. and a valve for said air connections controlled by said member incombination with a flask adapted to be seated and air-confined withinsaid receptacle.

8. In means for making castings by air pressure, a flask receptaclehaving an automatically operated member adapted to close the same,-and avalved air intake controlled by said member.

9. In means for making castings by air 11. In means for making castingsby air pressure, a flask receptacle having a pivoted cover and a sprinto close the same andmeans. to hold sai cover open against the tensionof said spring, and compressed air I connections for said receptacle.

12. In means for making cast1ngs-by a1r pressure, a flask receptaclehaving compressed air connections, a pivoted cover and,

a spring to close the same, a detaining lock for said cover, and an airintake valve engaged with said cover and adapted to open when the saidcover is closed.

13. In means for making castings by air pressure, a flask receptaclehavin a spring controlled cover and a detaining l ock therefor, an airintake for said receptacle and a valve operatively engaged with saidcover, and a vent open to the flask when confined within saidreceptacle.

14. In'means for making castings by air pressure, an open receptacleadapted to hold various sized flasks and having a vent opening in itsbottom, a self closing cover for said receptacle, and an automaticallyoperative air intake valve adapted'to open when the cover is closed.

15. In means for making castings by air pressure, an open receptacleadapted to hold mold flasks, a self closing cover for said receptacle,clamping means to hold said cover tightly shut, and a valve air intakefor said receptacle.

' lo. In means for making castings by air pressure. anropeu receptacleadapted to mold flasks-1a self-closing .coverior said receptacle andmeans to lock the same in closed position againstair pressure fromWithin, a

detaining member to hold said cover open, a

valved air intake for said receptacle, and a vent opening in the bottomof said receptacle adapted to he covered by the flask;

' ations. 4 i

18. In means forinaking castings by air pressure, a flask receptaclehaving an air chamber'adapted' touseat and confine a removable flask andhaving compressed air connections, and means towopen and close said airconnections automatically.

19. In means for making castings by air pressure, a flask receptaclehaving an air hold chamber adapted to seat and confine a removable flaskand having a cover and valved an connections, and automatic meansadapted to close the said valved connections upon opening the cover.

20. in means .t'or making castings by air pressure, a flask receptaclehaving a cover and valved air connections, means to auto,- maticallyclose said cover and open said valved air connections, and means toautomatically close said valved'air connections upon opening the cover.v 2.1. In a. pressure casting apparatus, the combination with thereceiver for the flask GDibOClYillg separable sections and a pressuresupply duct and valve controlled by the closing of the sections to admitpressure to the receiver, of a catch for holding'the receiver; closedagainst the internal pressure tending to open the same.

In testimony whereof I sign this specification in the presence of twoWitnesses this 9th day of July, 1907.

ORRIN J. SAYERS.

\Vitnesses F. J. LAUGER,

B. E. Mosnn.

e-imaLvmm

